- Clicking "image 1" should give you a full-size view. Not all circled stars may visible here because a higher magnification is required and/or my posted image is not as good as the original image I searched. However, in this view, there are roughly 50 to 100 specks that don't map to stars (including the foreground specks). So, about 75% of all the visible specs are stars, give or take.
- I like the blink-comparison viewing the hover-image after adjusting the browser magnification to 250% or higher.
APOD: Jets from Comet Churyumov-Gerasimenko (2015 Feb 03)
- alter-ego
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Re: Stars and Blobs
There's a question about how many, if any, stars are visible in today's APOD, and among all those specks and blobs are any bits from the comet? Certainly, specks visible in the foreground, within shadowed regions are not stars, and it will remain a question which of those are artifacts or real objects. However, in the region surrounding the comet, It's not fully appreciated how many bona-fide stars there are. In the hover image I circled >230 specks that match catalogued star positions typically < 2 arcminutes. The positions aren't exact mainly because I had to scale and rotate a Stellarium star field to match the specks in the APOD. I'll say that this only works if a star field has been identified. Random speck positions will in no way map to the degree they do here.
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Re: APOD: Jets from Comet Churyumov-Gerasimenko (2015 Feb 03
Nice work, Sleuthhound.
Just call me "geck" because "zilla" is like a last name.
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Re: APOD: Jets from Comet Churyumov-Gerasimenko (2015 Feb 03
Yeah, and a little bit o' luck!geckzilla wrote:Nice work, Sleuthhound.
Thanks geck!
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Re: APOD: Jets from Comet Churyumov-Gerasimenko (2015 Feb 03
Great work, alter-ego!
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Re: Stars and Blobs
YOU MISSED ONE!alter-ego wrote:There's a question about how many, if any, stars are visible in today's APOD, ... ... there are roughly 50 to 100 specks that don't map to stars (including the foreground specks).
Certainty is an emotion. So follow your spindle neurons.
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Re: Stars and Blobs
I admit I can get a terminator-like obsession for perfection, but what you say is true; most likely more the one. In fact, there were a few specks that I "deselected" because their change in position (still within the little yellow circle) I judged as anonymously high.FloridaMike wrote:YOU MISSED ONE!alter-ego wrote:There's a question about how many, if any, stars are visible in today's APOD, ... ... there are roughly 50 to 100 specks that don't map to stars (including the foreground specks).
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Re: APOD: Jets from Comet Churyumov-Gerasimenko (2015 Feb 03
Anybody have an explanation for the striations and clear curving/bending of the "jets"? They look suspiciously like being under magnetic field influence...
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Re: APOD: Jets from Comet Churyumov-Gerasimenko (2015 Feb 03
The jet curvature direction looks consistent with the rotation axis. I'm not aware of any magnetic field and wouldn't expect one from it of any significance. Like you spinning in a circle holding a water hose, ejected particles from the rotating comet follow the same dynamics. The video shows the comet from the other side. It is rotating counter-clockwise whereas in the APOD view, it is rotating clockwise. Therefore the jets would appear to be curving to the left.Mattunes wrote:Anybody have an explanation for the striations and clear curving/bending of the "jets"? They look suspiciously like being under magnetic field influence...
Click to play embedded YouTube video.
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